Possible Deviation From Specified Value During The Pressure Test (10 Of 11)

Possible Deviation from Specified Value during the Pressure Test
The required cooling output is only not attained at the evaporator for the battery cooling module components (the cooling output at the heater and A/C unit evaporator is OK). The high pressure corresponds to the specified value or increases only slightly (above pressure with engine stopped). Low pressure drops to specified value or lower.
Possible causes for the deviation from specified value and their solutions
Check the activation and function of the refrigerant shut-off valve 2, an adjustment motor, the blower or a temperature sensor in or on a battery cooling module is faulty service if necessary. use the Vehicle Diagnostic Tester in the"Guided Fault Finding" function of the A/C system and the battery regulation. Refer to Refrigerant Circuit . If the expansion valve for the expansion valve in the battery cooling module is faulty. -- Replace the expansion valve for the evaporator for battery cooling. Refer to Refrigerant Circuit .-- If no malfunction can be determined, check the function and activation of the components for battery cooling. Use the Vehicle Diagnostic Tester in the"Guided Fault Finding" function for the A/C system and check the battery regulation and refrigerant lines. Constriction or blockage in the refrigerant line either to or from the expansion valve on the evaporator for battery cooling. -- If there is a blockage clean the refrigerant circuit (flush with refrigerant R1234yf). Refer to REFRIGERANT CIRCUIT, CLEANING . Replace the expansion valve for the evaporator in the A/C unit (and for the evaporator for battery cooling) as well as the desiccant bag/dryer cartridge (or receiver/receiver/dryer). Refer to COMPONENTS, REPLACING and Refrigerant Circuit .-- If the hose or pipe is kinked or constricted, replace this component. Refer to Refrigerant Circuit . Not enough refrigerant in refrigerant circuit Extract refrigerant from the refrigerant circuit. Refer to REFRIGERANT CIRCUIT, DISCHARGING . If the extracted refrigerant quantity is significantly less than the specified capacity (more that 100 g (3.5 oz)). Refer to Technical Data , and look for leaks and correct. Refer to LEAKS, FINDING . If the extracted refrigerant quantity corresponds to the capacity or is only slightly smaller (maximum 100 g (3.5 oz)). Refer to Technical Data , refrigerant shut-off valve 1. Use the Vehicle Diagnostic Tester in the"Guided Fault Finding" function for the A/C system function and the battery regulation. Refer to Refrigerant Circuit .
Final Procedures
-- Charge the refrigerant circuit. Refer to REFRIGERANT CIRCUIT, CHARGING .-- Repeat the test. Refer to ELECTRICALLY-DRIVEN A/C COMPRESSOR, CHECKING PRESSURE WITH A/C SYSTEM SWITCHED ON .

NOTE:

For cooling the Electric Vehicle Battery -A2- (hybrid battery) the refrigerant shut-off valve 1 is currently activated from a specific battery temperature for example from the battery regulation control module. If the A/C system driver is not already activated at this time, the Electrical A/C Compressor -V470- is activated via the A/C Compressor Control Module -J842- for example by the battery regulation control module. The temperature of the air (or the coolant) before and after the evaporator for battery cooling module is calculated by the respective control module (for example by the battery regulation control module). If at the same time it is determined that the cooling is not sufficient this is stored for example in the battery regulation control module. Use the Vehicle Diagnostic Tester in the"Guided Fault Finding" function of the A/C system and the battery regulation.

The temperature of the air (or the coolant) and the evaporator cooling output in the battery cooling module is determined via the installed temperature sensor (it currently cannot be measured using a thermometer while operating) and may only for this reason be checked using the Guided Fault Finding. Use the Vehicle Diagnostic Tester in the"Guided Fault Finding" function of the A/C System and the battery regulation.

Refer to Possible Deviation From Specified Value During The Pressure Test (1 Of 11) for further information.